The present disclosure relates to respiratory masks. Respiratory masks are used in several different situations for treatment of respiratory disorders, for example obstructive sleep apnea. During treatment, a flow of breathable gas is provided to a patient through the mask. Current mask designs generally include a mask frame or body coupleable to a conduit that delivers the breathable gas flow. A cushion is coupled to the mask frame and presses against the patient to provide comfort and cover the nose and/or mouth of the patient. Additionally, a forehead pad can be provided for cushioning the mask against the forehead of the patient. Straps are provided to secure the mask to the patient's head.
One concern in mask design is assembly of mask components. In some instances, masks utilize a retaining ring to secure the cushion of the mask to the mask frame. One method of securing the cushion to the mask frame includes ultrasonically welding the retaining ring to the mask frame so as to permanently secure the cushion to the mask frame. The ultrasonic welding process requires tools to assemble the mask, which can add to the cost of the mask. Furthermore, while this method is effective in securing the cushion to the mask frame, there are additional disadvantages in having the cushion permanently secured to the mask frame. For example, some insurance companies only reimburse a patient for cushion replacement on a regular basis. Permanent assembly of the cushion to the mask frame prevents the patient from only replacing the cushion. Due to the lack of reimbursement, the patient, in some instances, will defer replacement of the mask or have to pay for a new mask out-of-pocket. Furthermore, the mask can be difficult to clean when the cushion and mask frame are assembled, leading to potentially unsanitary conditions.
In another method of securing the cushion to the mask, a separate retaining ring secures the cushion around its edges by utilizing a tongue and groove connection on either the outside or inside of the cushion. In yet another method, the cushion can be secured to the mask frame by sandwiching the cushion edge between the mask frame and the retaining ring. In any event, by utilizing a retaining ring that is separate from the cushion, securing the cushion to the mask frame can be cumbersome and time consuming. For example, it may be difficult to properly align the cushion and the retaining ring so as to properly secure the cushion to the mask frame.
Another concern in mask design is comfort to the patient. Current masks can be uncomfortable and unable to accommodate different shapes and/or sizes of heads. For example, forehead pads can be stiff and thus not conform to various foreheads. In other masks, forehead pads can be adjustable, but many masks are difficult to conform to different shapes and/or sizes of heads and thus not desirable. Additionally, forehead pads may be formed of a material that retains water. As a result, water may be retained in the forehead pad after cleaning. Further still, perspiration from the patient can be retained in the forehead pad. Both of these situations can lead to unsanitary conditions.